• Journal of Environmental Science International
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• v.10 no.4
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• pp.293-298
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• 2001

The toxicity values heavy metals were evaluated by immobilization and chronic reproduction impairment tests, using Daphnia magna. Acute tests were evaluated by the inhibition of their mobilization after 24hrs without food addition. The tests of reproductive impairment were investigated for 21 days by food addition and exchange or water. The effect of each concentration was assessed by Probit analysis and t-test. The results obtained from this study were as follows : 1) The change of pH and DO was not significant in the acute tests, while, in the reproductive tests, pH was increased by 0.3~1.4 and DO also increased. 2) The $E_iC_{50}$ values of immobilization to Daphnia magna in artificial fresh water were $0.030mg/{\ell}(Cu),\;0.054mg/{\ell}(Cd),\;0.12mg/{\ell};(Cr),\;0.74mg/{\ell}(Pb),\;3.4mg/ {\ell}(As)$ and the $NOE_iC$ values were $0.010mg/{\ell}(Cu),\;0.018mg/{\ell}(Cd),\;0.010mg/{\ell}(Cr),\;0.10mg/{\ell}(Pb),\;and\;$1.8mg/{\ell}(As)$. 3) The $E_rC_{50}$ values of reproductive impairment to Daphnia magna were $13.8\mu\textrm{g}/{\ell}(Cu),\;2.9\mu\textrm{g}/{\ell}(Cd),\;15.5\mu\textrm{g}/{\ell}(Cr),\;61.7\mu\textrm{g}/{\ell}(Pb),\;759\mu\textrm{g}/{\ell}(As)$, and $NOE_rC$ values were $0.95\mu\textrm{g}/{\ell}(Cu),\;$0.54\mu\textrm{g}/{\ell}(Cd),\;1.2\mu\textrm{g}/{\ell}(Cd),\;$7.4\mu\textrm{g}/{\ell}(Pb),\;110mu\textrm{g}/{\ell}(As)$. The results of tests using OECD artificial culture water were more sensitive than natural water for culturing. The presented data show that an artificial culture water is suitable in the experiment of bioassay for assessing the toxicity of marterials.

• Transactions on Electrical and Electronic Materials
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• v.13 no.4
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• pp.196-199
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• 2012

CdS thin film was prepared on glass substrate by chemical bath deposition in an alkaline solution. The optical properties of CdS thin film were investigated using spectroscopic ellipsometry. The real (${\varepsilon}_1$) and imaginary (${\varepsilon}_2$) parts of the complex dielectric function ${\varepsilon}(E)={\varepsilon}_1(E)+i{\varepsilon}_2(E)$, the refractive index n(E), and the extinction coefficient k(E) of CdS thin film were obtained from spectroscopic ellipsometry. The normal-incidence reflectivity R(E) and absorption coefficient ${\alpha}(E)$ of CdS thin film were obtained using the refractive index and extinction coefficient. The critical points $E_0$ and $E_1$ of CdS thin film were shown in spectra of the dielectric function and optical constants of refractive index, extinction coefficient, normal-incidence reflectivity, and absorption coefficient. The dispersion of refractive index was analyzed by the Wemple-DiDomenico single-oscillator model.

• Analytical Science and Technology
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• v.18 no.5
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• pp.391-395
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• 2005

The title complex, $[Cd(N_3)_2(2-ethylimidazole)_2]$, I, has been prepared and characterized by X-ray single crystallography. The complex I crystallizes in the monoclinic system, Cc space group with a = 16.200(3), b = 12.926(3), $c=7.007(1){\AA}$, ${\beta}=102.29(3)^{\circ}$, $V=1433.7(5){\AA}^3$, Z = 4, $R_1=0.0239$ and ${\omega}R_2=0.0604$ for 1874 independent reflections. Cd(II) atom has a slightly distorted octahedral coordination geometry, with four end-on (${\mu}-1$,1) bridging azido ligands and two 2-ethylimidazole ligands bonding through nitrogen atom. The central cadmium(II) atoms are run in parallel to the c-axis and are doubly bridged with neighboring cadmium(II) atoms by the end-on (${\mu}-1$,1) bridging azido ligands. Thus, this complex has a one-dimensional zigzag chain structure in which the 2-ethylimidazole is in the cis conformation.

• The Journal of Korean Medicine
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• v.22 no.3
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• pp.156-168
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• 2001

Objectives : To evaluate the diverse actions of stimulation on the hematopoietic system, 4 formulas (KH I, KH 2, KH 3, KH 4) were studied. Method and Result : RT-PCR was performed to measure the gene expression of hematopoietic cytokines (TPO, GM-CSF, SCF, IL-3). When bone marrow cells were treated with KH 1, 2, 3, 4, the gene expressions of TPO, SCF, IL-3, and GM-CSF were increased. Flow cytometric analysis was performed to measure the expression of CD34+ cell activity. After 72 hrs culture supplemented with KH 1, 2, 3, 4, the percent of CD34+ cell of KH 2, 3, 4 were increased. To measure the expression of colony forming units - granulocyte erythrocytes, macrophages, megakaryocytes (CFU-GEMM) and burst forming unit-erythroid (BFU-E), semisolid clonogenic assay was performed. After 14 days of culture the number of CFU-GEMM and BFU-E of KH I, 2, 3, 4 were significantly increased compared to those of EPO groups (KH 1 P<0.0l, KH 2 P<0.05, KH 3 P<0.001, KH 4 P<0.0l). To determine the intracelluar TPO expression by KH 3, KH 4 in bone marrow cells, intracelluar staining and flow cytometric analysis were performed. After 24 hrs cultures, the TPO expression of the KH 3 and KH 4 treated groups were increased over those of the controlled groups (control : 50%, KH 3 : 87%, KH 4 : 78%). Conclusion : These results suggest that KH I, KH 2, KH 3, KH 4 have hematopoietic effects through increasing the production of hematopoietic cytokines and stimulating the activity of $CD34^{+}$ cells. This study also shows that KH 3 has a more effective hematopoietic effect than KH 1, 2, 4. These results suggest that the formulas (KH I, 2, 3, 4) can be applied to the patients with inappropriate hematopoietic system, and that KH 3 can be the most effective formula among these 4 in treating bone marrow disease in clinics.

• Journal of Nutrition and Health
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• v.26 no.3
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• pp.286-298
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• 1993

In order to investigate the effect of selenium (Se) on the liver damage, metallothionein synthesis and hepatic antioxidative detoxification system in cadmium(Cd) administered rats. Sprague-Dawley male rats(60\\5g) were divided into two diet groups, depending on with (CdS groups) or without (Cd groups) 0.5ppm Se supplementation and fed experimental diets ad libidum for 4 weeks. And then each group was again subdivided into five groups, depending on injection number of Cd, i.e., 0, 1, 2, 3, and 4 times of 2.5mg Cd/kg of body wt once a day. Hemoglobin concentration, hematocrit values, superoxide dismutase, glutathione peroxidase and glutathione S-transferase activite were decreased progressively with increasing number of Cd injection, but increased by the supplementation of Se. The reduced form of glutathione (GSH) contents in blood and liver and vitamin E content were decreased and oxidized form (GSSG) increased in Cd groups, but these of Se supplemented groups were not very different from controls. Cd reduced liver vitamin E content which was not restored by Se supplementation. Liver lipid peroxide values were elevated with increasing doses of Cd, but Se supplementation reduced these elevated levels. Accumulation of metallothionein in liver and kidney was increased with increasing number of Cd injection, but Se did not affect on them. Histological examination revealed that lysosomes were significantly increased and mitochondria and Golgi apparatus were enlarged by Cd, however, these changes were reduced by Se. It was concluded that Se administration promoted antioxidative detoxification and alleviated peroxidative damage in rat liver by Cd.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1645-1647
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• 1996

Polycrystalline CdTe thin films -have been studied for photovoltaic application because of their high absorption coefficient and optimal band gap energy (1.54 eV) for solar energy conversion. In this study, we prepared CdTe films using RF-magnetron sputtering method and investigated structural, optical and electrical properties with spectrophotometer, XRD, EDX, and resistivity meter. CdTe films at $200\;^{\circ}C$ showed a mixture of zinc blend (Cubic) and wurtzite (hexagonal) phase. On the other hand, the films at $400\;^{\circ}C$ showed highly oriented structure having hexagonal structure. The resistivity of CdTe films deposited on $SiO_2$ substrates was about $10_7\;{\Omega}cm$. The value of resistivity decreased with the increase of the substrate temperature. CdTe were sputtered on CdS thin films prepared by chemical bath deposition for the formation of the heterojunction. I-V characteristics of these cells were measured at a light density of $100mw/cm^2$, AM. 1.0. The present thin film solar cells showed a conversion efficiency of about 5%.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1418-1420
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• 1996

In this paper, structural properties of CdTe thin films and photovoltaic properties of thin film CdS/CdTe solar ceIl prepared by thermal vacuum evaporation were studied. Structural variation with $CdCl_2/heat$ treatment are assessed using x-ray diffraction and scanning electron microscopy. The crystal structure of CdTe films was zincblend type with preferential orientation of the (111) plane parallel to the substrate. The $CdCl_2$ treatment appears to increase the grain size of polycrystalline CdTe thin film. It was found that CdS/CdTe solar cell characteristics were improved by the heat treatment with $CdCl_2$. The conversion efficiency, however, decreased when heat treatment temperature was too high.

• Current Photovoltaic Research
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• v.1 no.1
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• pp.52-58
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• 2013

Two different window-structured $CuInGaSe_2$(CIGS) solar cells, i.e., CIGS/thin-CdS/ZnO:B(sample A) and CIGS/very thin-CdS/Zn(S/O)/ZnO:B(sample B), were prepared, and the diffusivity of Zn, Cd, S, and B atoms, respectively, in the CIGS, ZnO or Zn(S/O) layer was estimated by a theoretical fit to experimental secondary ion mass spectrometer data. Diffusivities of Zn, Cd, S, and B atoms in CIGS were $2.0{\times}10^{-13}(1.5{\times}10^{-13})$, $4.6{\times}10^{-13}(4.4{\times}10^{-13})$, $1.6{\times}10^{-13}(1.8{\times}10^{-13})$, and $1.2{\times}10^{-12}cm^2/s$ at 423K, respectively, where the values in parentheses were obtained from sample B and the others from sample A. The diffusivity of the B atom in a Zn(S/O) of sample B was $2.1{\times}10^{-14}cm^2/sec$. Moreover, the diffusivities of Cd and S atoms diffusing back into ZnO(sample A) or Zn(S/O)(sample A) layers were extremely low at 423K, and the estimated diffusion coefficients were $2.2{\times}10^{-15}cm^2/s$ for Cd and $3.0{\times}10^{-15}cm^2/s$ for S.

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.25-30
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• 1987

This study was conducted to find out the effect of several improvers such as triple super phosphate, slaked lime, wollastonite and gypsum for reducing Cd content in brown rice. Several improvers were applied to two different types of soils which are contaminated with copper-zinc mine wasted and sludge.(Soil I contained Cd : 7.88, Cu : 57.9, Zn : 175.0 ppm, Soil II contained Cd : 3.95, Cu : 30.2, Zn :124.0 ppm) In general, effects of improvers on reducing content of Cd, Cu and Zn in brown rice were greater in soil I than soil II. In soil I, the Cd content of brown rice was reduced to 0.4ppm below by application of triple superphosphate, fused phosphate, slaked lime and gypsum, 98, 225, 190 and 276Kg/10a, respectively. Triple superphosphate was more effective than fused phosphate in reducing uptake of Cd, Cu and Zn by applying them as an equal amount of phosphorous, also to equal alkalinity, slaked lime had the highest effect. Negatively linear effect was found between soil pH and Cd and Zn content in brown rice. As to above results, it was no doubt that triple superphosphate, fused phosphate and slaked lime would be applied to reduced heavy metals in brown rice. The slaked lime, triple super phosphate and fused phosphate were available to reduce uptake of Cd, Cu and Zn by rice plant grown in the soil contaminated with mine waste and sludge.

• Analytical Science and Technology
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• v.12 no.2
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• pp.105-110
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• 1999

The studies on the adsorption properties and the antibacterial effects of the Cd and Cu-treated activated carbon were carried out. From the adsorption studies on the series of these metal-treated activated carbons, typical Type-I isotherm was observed. The surface areas of the treated carbon obtained from BET equation were in the range of $1101-1418m^2/g$ for Cd-AC and of $1084-1361m^2/g$ for Cu-AC. Using ${\alpha}_s$-plot, the micropore volumes and pore size distribution were obtained. From the SEM study, it is also observed that many of micropores in activated carbon are blocked by window blocking effect of metals after the impregnation. Finally, antibacterial effects of M-activated carbon against Escherichia coli was discussed. From the study, the area of antibacterial activity becomes larger with the increase of the amount of metal treated.